1. Field of the Invention
The present disclosure relates generally to heat transfer and heat dissipation techniques, and in particular but not exclusively, relates to removal of heat generated from a hand-held device, such as a portable computer, by transferring and dissipating the heat from non-hand-held regions of the device.
2. Description of the Related Art
Many laptops or other hand-held devices create 10-30 watts of power from processors, graphics systems, disk drives, memory systems, display drivers, backlights, and other components. This generated power is in the form of heat that must be moved away from the heat-generating chip(s) to the outside of the device. Failure to properly dissipate the heat can lead to device failure, permanent damage to the device, and potential fire or burn injury to a user.
Modern laptops use heat-pipes, heat sinks, and fan(s) to pull the heat to the outside surface or air. Newer smaller personal computers (PCs), such as sub-notebooks and ultra-portable computers, have three primary issues that influence their design and operation. First, as compared to conventional-sized PCs, it is more difficult to build extremely small devices while still leaving sufficient room for airflow. Second, it is difficult and undesirable to have a fan running in the device, due to size, weight, power, and noise issues. Third, these smaller devices have a significantly smaller surface area (in many cases less than ¼ of the area of a conventional-sized PC) to dissipate heat, which results in far higher temperatures on surfaces, thereby potentially causing burning (of the user's skin, for instance) or external fire.
Many of these newer and smaller devices are taking advantage of newer integrated chip (IC) technology that allows less power dissipation per task. Smaller device geometries on IC require lower voltages that allow lower heat generation. They can also allow higher performance, but a trade-off must be made between using the available additional performance against the heat that would be generated. Therefore, many solutions have opted for lower performance and lower voltage operation to solve these heat dissipation issues. This is unfortunate for users because such devices are losing the opportunity to provide higher performance.